1. Field of the Invention
The present invention relates to an apparatus for everting a lining material, and particularly relates to an apparatus for everting and inserting a tubular pipe-lining material into a deteriorated underground pipeline to line and rehabilitate the interior surface thereof.
2. Description of the Prior Art
There are pipe lining methods for lining the interior of sewage pipes, gas pipes, communication cable pipes, power cable pipes, and other deteriorated underground pipes and repairing the pipes without unearthing the pipes from the ground.
A known example of such above-described pipe lining methods is to use a pipe-lining material composed of a tubular resin-adsorbing material that is covered at its external surface with an airtight plastic film and is impregnated with an uncured liquid curable resin. In this method, the pipe-lining material is everted and inserted into a pipeline by fluid pressure using a lining material everting apparatus, and the curable resin impregnated in the pipe-lining material is thereafter cured in a state in which the pipe-lining material is inflated by fluid pressure and pressed to the inner surface of the pipeline.
Ordinarily, the pipe-lining material is stored in a storage container with an airtight structure in which the material is flattened and folded. One end of the pipe-lining material stored in the storage container is curved outward, connected to the storage container, and mounted on the external periphery of the opening end of an everting nozzle. Fluid pressure acts inside the storage container and the material is inserted into the pipeline while being everted (Japanese Laid-open Patent Application 2003-165158).
With a conventional lining material everting apparatus, the pipe-lining material is folded and stored in a storage container prior to being everted. Therefore, the resistance of being drawn out of the container during eversion is considerable, and there is a problem in that a considerable everting force is required.
Also, since the pipe-lining material is folded and stored, there is problem in that the upper portion of the folded pipe-lining material shifts up and down in accordance with the amount drawn out during the operation, and the drawing out process cannot be smoothly carried out.
When working with a conventional lining that is to be disposed in an existing pipeline, the everting nozzle is mounted in the vertical direction, and the pipeline to be repaired extends horizontally. Therefore, the pipe-lining material everted by the everting nozzle is curved at the location in which the direction of the material changes from the vertical to horizontal direction. This causes considerable friction to be generated, resulting in eversion resistance. In particular, the lining material may stop everting partway in the process when the lining material has considerable thickness and a large amount of everting pressure is required, or when the lining material is heavy because of a large diameter.
It is therefore an object of the present invention to provide an apparatus that enables a lining material to be smoothly and reliably everted and inserted into an affected pipeline without stopping the lining process partway.